In recent years, telephone networks have been installed throughout most of the industrialized world. Initially, this telecommunication infrastructure was implemented through a land-based or landline system known as the public switched telephone network (PSTN). The landline PSTN transmits telephone calls over land-based lines, such as copper wires and fiber optic cables. Communication devices that operate in the landline PSTN, such as telephones and other devices that have telephone equipment within them, are typically referred to as landline or wireline units or telephones.
More recently, a wireless telecommunications infrastructure has been installed in addition to the previously existing landline PSTN. Although these two systems are functionally integrated, there remain some important distinctions. First, wireline units typically remain stationary because they are tied to land-based telephone lines. Wireless units, on the other hand, typically travel from place to place with the owner. For example, many wireless units are configured for installation in automobiles and others are configured to be carried on one's person. Second, wireline telephone service has not traditionally included time-based charges for many services, whereas wireless telephone service has typically involved time-based or “air time” charges for virtually all uses of the wireless telephone.
Specifically, landline telephone service has not traditionally involved time-based charges for received telephone calls. In additional, local landline telephone service has traditionally been provided on a flat-rate basis, which avoids time-based charges for local originated telephone calls. The result of these landline billing policies is that only originated long-distance telephone calls have traditionally involved time-based charges in the landline PSTN; local telephone calls and received long distance calls have not traditionally involved time-based charges. Wireless telephone service, on the other hand, has typically involved time-based or “air-time” charges for virtually all uses of the wireless telephone. This usually means that receiving a telephone call on one's wireless unit is a more expensive option than receiving the same telephone call on a wireline unit.
The practical result of these differences in wireline and wireless billing practices has been to encourage many people to receive telephone calls on wireline units whenever possible, and to use their wireless units only when landline service is unavailable. For example, to save air-time charges, some subscribers may ask calling parties to call them first at a landline telephone number, and if they don't answer, then them try them at a wireless telephone number. In addition, if a wireless telephone call is received while the called party is near a landline telephone, the called party may ask the calling party to hang up and a call back on the landline telephone.
Many telephone service subscribers find these practices cumbersome because calling parties must know multiple telephone numbers for reaching the subscriber. In response, telephone service providers have offered “personal number” or “one number” telephone services, which allow calling parties to dial a single telephone number to reach a subscriber on a predefined set of wireline and/or wireless telephones. To implement this service, the telephone service provider takes control over all telephone calls directed to the subscriber's “one number,” and rings the calls on the various telephones in a predefined order. That order may vary based on the time of day, day of week, and other factors, such as whether a particular wireless unit is powered on, whether a particular wireless unit is present in a particular location, whether a particular wireless unit has been placed in its battery charger, and so forth. For example, the subscriber may instruct the service provider to ring an incoming telephone call first on the subscriber's wireline, and if that unit is not answered, to ring the call on the subscriber's wireless unit.
While this type of “one number” service is effective at reducing air-time charges, it has a number of drawbacks. First, the service provider must be given advance notice of all of the directory numbers for trying to reach a particular subscriber. Although the subscriber may give the service provider several wireline directory numbers where the subscriber is frequently located, such as home and work, the “one number” service will not be able to reach the subscriber on wireline units at other locations that the subscriber visits less frequently. Second, calling parties often experience delays while the service provider rings at a first location, then at a second location, an so forth. Third, taking control over incoming telephone calls occupies telecommunication resources and, as a result, “one number” service typically involves a premium charge.
To overcome these disadvantages, telephone service providers may offer simplified telephone call forwarding. For example, some wireless telephone service plans allow a subscriber to easily forward telephone service using a predefined code, such as “*71+ forwarding number.” The forwarded wireless service can later be unforwarded using another predefined code, such as “*72.” This allows the subscriber to quickly forward incoming wireless telephone calls to a wireline unit while the subscriber is located near the wireline unit. When the subscriber leaves the area, he or she can quickly unforward the wireless telephone service.
Although this type of simplified call forwarding service has certain advantages, many wireless subscribers fail to use it effectively. In many cases, the subscribers simply fail to take the time to learn the forwarding and unforwarding codes. In other instances, subscribers may forget to enter the required forwarding code. And in other situations, it may be inconvenient for the subscriber to ask for or look up the telephone number of a wireline unit where the subscriber is temporarily located. That is, many people won't go to the trouble of forwarding their wireless telephone service if they have to look up or ask for the forwarding number. As a result, even simplified forwarding services are used most often with wireline directory numbers that the wireless subscriber has memorized.
Accordingly, there is a need for even more convenient ways to temporarily forward wireless telephone service. In particular, there is a need for convenient ways to forward wireless telephone service to wireline units in locations that the wireless subscriber visits infrequently.